Helga Gardarsdottir appointed Professor of Real World Data for Decision Making on Medicines

Utrecht University has appointed Helga Gardarsdottir as Professor of Real World Data for Decision Making on Medicines. Gardarsdottir and her team investigate how so called "real world data", including healthcare data from routine practice, can be used more effectively to gain insights into the safety and effectiveness of medicines, in order to enable well-informed clinical and regulatory decisions.

Before a medicine is approved for the market, it undergoes testing to assess its safety and efficacy. This is done in so-called clinical trials. But these studies, which are meticulously controlled, have their limitations. They may not always represent the group of people that ends up using the medicine, such as pregnant women, children and the elderly. Also, the medicine’s use in clinical studies may not mirror real-world usage. Moreover, clinical studies typically have short durations, leaving uncertainties regarding the medicine’s long-term safety.

Much more data

Data from daily practice are already contributing to the understanding of (long-term) medicine effectiveness and safety, Gardarsdottir highlights. However, recent advancements offer even greater potential. Gardarsdottir: "Previously, we mainly relied on data from clinical practice such as information from pharmacies and general practitioners. Currently, there is a wealth of additional data being generated, including information gathered from wearables like smartwatches. Moreover, new technologies such as artificial intelligence provide an opportunity for us to improve the use of less structured data, such as physician notes. These developments are going to have a significantly impact in the future."


The use of real world data for informing clinical and regulatory decisions is currently receiving significant attention. Gardarsdottir: "While many stakeholders are eager to make more use of this type of data, there are also critics of its usage. Evidence generated with real world data is not going to replace that from clinical trials. It should be seen and used in a complementary manner."

The value of real world data was underscored during the COVID-19 pandemic, where it for instance was used to gain insights into patient characteristics among COVID-19 cases and for assessing the safety and effectiveness of COVID-19 vaccines.

Evidence generated with real world data is not going to replace that from clinical trials. It should be seen and used in a complementary manner.

Helga Gardarsdottir


Gardarsdottir and her team use real world data to enable healthcare providers and regulatory bodies to make well-informed decisions about treatment. At the European level, the European Medicines Agency (EMA) is responsible for regulation of medicines.

Gardarsdottir is one of the founders of the European Pharmacoepidemiology and Pharmacovigilance (PE & PV) Research Network, which conducts studies commissioned by the EMA. They explore questions like: Are certain patients using medicines they should not be? Are there any new side effects that warrant a reassessment of the medicine’s usage? For example, Gardarsdottir spearheaded a large international study examining the risk of bleeding associated with the use of a relatively new anticoagulant prescribed to patients with cardiovascular disease.

When regulations change, it remains to be seen how things play out in practice. Will physicians adopt their prescribing behaviour accordingly, and what factors influence their decision-making? Moreover, what unintended consequences might arise from these regulatory decisions? Gardarsdottir: "For instance, if a decision is made that a medicine should not be used by certain patients, the patient still requires treatment, often leading to the use of an alternative medicine. But is this alternative truly better for the patient, or does it introduce other, possibly greater, risks?" Gardarsdottir and her team are actively developing and testing new methods to improve transparency in such situations.


Together with Dutch and European colleagues, Gardarsdottir is also working on better understanding and improving how real world data on a European level is analysed. She acknowledges that this is a complex task, as differences between countries can be large.

The Icelandic researcher, who studied in Sweden and settled in the Netherlands after obtaining her PhD there, expresses fascination with these differences. Her own experiences with various healthcare systems help her to understand the origins of disparities within the data she investigates.

"Each country has their own way of making decisions, resulting in differences in healthcare provision and availability of medicines," Gardarsdottir explains. In her teaching, Gardarsdottir makes sure that her students are aware of this. And drawing from her own enriching experiences abroad, she also encourages her students to gain experience in other countries and research environments.

Diversity and inclusion

Gardarsdottir’s Icelandic perspective also offers a fresh take on how things are done in the Netherlands on a broader scale. When she was pregnant as a PhD candidate, some Dutch people asked her if she considered to quit her job. Gardarsdottir: "That was a bit of a shock to me. In Iceland, no one would have posed that question. And, by the way, nobody asked my husband that either."

As the chair of the Equality, Diversity and Inclusion committee of the Faculty of Science, Gardarsdottir is dedicated to enacting policies that foster a more inclusive and diverse environment. "In Iceland, discussions about caregiving responsibilities or career adjustments are never tied to biological sex or gender. Iceland accordingly tops the Global Gender Gap Index , indicating minimal disparities between women and men. The Netherlands, by contrast, ranks 28th. Individuals of course must make their own decisions, but in that perspective, there is still a lot to gain."